Estimate a line-of-sight radio coverage radius for an edge network using a simplified log-distance path-loss model. The calculator builds an allowable path-loss budget from transmitter power, antenna gains, receiver sensitivity, and system losses, then applies frequency and environmental path-loss assumptions. Use the result for scenario screening—not as a substitute for a site survey or regulatory review.
The result is the modeled distance at which received power reaches the sensitivity threshold under the selected path-loss exponent. Coverage can be shorter in clutter, below ground, indoors, or near interference.
A valid link also depends on legal transmit-power limits, antenna height and pattern, Fresnel-zone clearance, noise, interference, modulation, duty cycle, and required reliability.
At 20 dBm transmit power, 2 dBi antennas, −100 dBm sensitivity, 915 MHz, path-loss exponent 2.7, and 10 dB losses, allowable path loss is 114 dB. The modeled radius is about 1.12 km (0.69 miles).
Reference free-space path loss rises with frequency, reducing distance when the rest of the link budget is unchanged.
Use a value measured in a similar environment. Two represents ideal free space; cluttered environments generally require a larger value.
Antenna gain increases EIRP, which may be regulated. Confirm the applicable regional limit before deployment.
No. Sensitivity commonly changes with modulation, bandwidth, and data rate, so use the value for the intended operating mode.
Only as a rough scenario if losses and exponent are calibrated. Building penetration and underground propagation need site-specific modeling and tests.
| Variable | Meaning | Unit |
|---|---|---|
| L | Allowable path loss | dB |
| f | Carrier frequency | MHz |
| n | Path-loss exponent | ratio |
| d | Modeled radius | m or km |